Roger Federer is well aware he will face a very different Andy Murray in the Wimbledon semi-finals to the one the world number two crushed at the World Tour Finals last December.

It took the Swiss maestro just 56 minutes to thrash Murray 6-0 6-1 as the Scot's 2014 season ended in a whimper.

Federer defeated Gilles Simon 6-3 7-5 6-2 on Wednesday to set up a last-four meeting with Murray " who has reached the Australian Open final and French Open semi-finals this year " a match the seven-time Wimbledon champion is relishing.

Reflecting on the duo's previous encounter at London's O2 Arena, Federer said: "I thought World Tour Finals, he came in tired.

"You know, he had won three tournaments back to back to back. He left everything out there, making the World Tour Finals.

"I think when I played him, he was a bit cooked, to be honest. I played a great match, but it was not the Andy that usually comes up and shows up.

"He's in full flight right now."

Victory over Simon was comfortable for Federer, whose streak of 116 consecutive service holds in all competitions came to an end.

He added: "I don't keep count when I'm out there.

"I'm just trying to focus on the next service game, on the next point, the next serve.

"I'm happy it lasted as long as it did. I'm very happy to be in the semis again.

"The road is long getting here. But still I feel like I'm fresh and I've got energy left in the tank for hopefully a great match with Andy and then we'll see."